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Category Archives: Eurasian colonization

Ancient DNA from Clovis culture is Native American (also Tianyuan affinity mystery)

Figure 4 | [c] (…) maximum likelihood tree. 
A recent study on the ancient DNA of human remains from Anzick (Montana, USA), dated to c. 12,500 calBP, confirms close ties to modern Native Americans, definitely discarding the far-fetched and outlandishly Eurocentric “Solutrean hypothesis” for the origins of Clovis culture (what pleases me greatly, I must admit).
While this fits well with the expectations (at least mine), there is some hidden data that has surprised me quite a bit: it sits at the bottom of a non-discussed formal test graph in which modern populations are compared with both Anzick and Tianyuan (c. 40,000 BP, North China). See below.
Morten Rasmussen et al., The genome of a Late Pleistocene human from a Clovis burial site in western Montana. Nature 2014. Pay per viewLINK [doi:10.1038/nature13025]

Abstract


Clovis, with its distinctive biface, blade and osseous technologies, is the oldest widespread archaeological complex defined in North America, dating from 11,100 to 10,700 14C years before present (bp) (13,000 to 12,600 calendar years bp)1, 2. Nearly 50 years of archaeological research point to the Clovis complex as having developed south of the North American ice sheets from an ancestral technology3. However, both the origins and the genetic legacy of the people who manufactured Clovis tools remain under debate. It is generally believed that these people ultimately derived from Asia and were directly related to contemporary Native Americans2. An alternative, Solutrean, hypothesis posits that the Clovis predecessors emigrated from southwestern Europe during the Last Glacial Maximum4. Here we report the genome sequence of a male infant (Anzick-1) recovered from the Anzick burial site in western Montana. The human bones date to 10,705 ± 35 14C years bp (approximately 12,707–12,556 calendar years bp) and were directly associated with Clovis tools. We sequenced the genome to an average depth of 14.4× and show that the gene flow from the Siberian Upper Palaeolithic Mal’ta population5 into Native American ancestors is also shared by the Anzick-1 individual and thus happened before 12,600 years bp. We also show that the Anzick-1 individual is more closely related to all indigenous American populations than to any other group. Our data are compatible with the hypothesis that Anzick-1 belonged to a population directly ancestral to many contemporary Native Americans. Finally, we find evidence of a deep divergence in Native American populations that predates the Anzick-1 individual.

Haploid DNA
The Y-DNA lineage of Anzick is Q1a2a1* (L54) to the exclusion of the common Native American subhaplogroup Q1a2a1a1 (M3). Among the modern compared sequences that of a Maya is the closest one.

The mtDNA belongs to the common Native American lineage D4h3a at its underived stage (root). 
For starters I must explain that these underived haplotypes can only be found within mtDNA and never in modern Y-DNA (common misconception) because this one accumulates mutations every single generation, while the much shorter mtDNA does only occasionally. Hypothetically we could find the exact ancestor of some modern Y-DNA haplogroup in ancient remains but that would be like finding the proverbial needle in the haystack. On the other hand, finding the underived stage in mtDNA, be it ancient or modern, does not mean that we are before a direct ancestor but just a non-mutated relative of her, who can be very distant in fact.


Autosomal DNA

In this aspect, the Anzick man shows clearly strongest affinities to Native Americans, followed at some distance by Siberian peoples, particularly those near the Bering Strait. 

Figure 2 | Genetic affinity of Anzick-1. a, Anzick-1 is most closely related to Native Americans. Heat map representing estimated outgroup f3-statistics for shared genetic history between the Anzick-1 individual and each of 143 contemporary human populations outside sub-Saharan Africa. (…)
However Anzick-1 shows clearly closer affinity to the aboriginal peoples of Meso, Central and South America (collectively labeled as SA) and less so to those of Canada and the American Arctic (labeled as NA). No data was available from the USA. 
This was pondered by the authors in several competing models of Native American ancestry:
Figure 3 | Simplified schematic of genetic models. Alternative models of the population history behind the closer shared ancestry of the Anzick-1 individual to Central and Southern American (SA) populations than Northern Native American (NA) populations; seemain text for further definition of populations. We find that the data are consistent with a simple tree-like model in which NA populations are historically basal to Anzick-1 and SA. We base this conclusion on two D-tests conducted on the Anzick-1 individual, NA and SA. We used Han Chinese as outgroup. a, We first tested the hypothesis that Anzick-1 is basal to both NA and SA populations using D(Han, Anzick-1; NA, SA). As in the results for each pairwise comparison between SA and NA populations (Extended Data Fig. 4), this hypothesis is rejected. b, Next, we tested D(Han, NA; Anzick-1, SA); if NA populations were a mixture of post-Anzick-1 and pre-Anzick-1 ancestry, we would expect to reject this topology. c, We found that a topology with NA populations basal to Anzick-1 and SA populations is consistent with the data. d, However, another alternative is that the Anzick-1 individual is from the time of the last common ancestral population of the Northern and Southern lineage, after which the Northern lineage received gene flow from a more basal lineage.
The most plausible model they believe is “c”, in which Anzick-1 is close to the origin of the SA population, while NA diverged before him. However model “d” in which Anzick-1 is close to the overall Native American root but NA have received further inputs from a mystery population (presumably some Siberians, related to the Na-Dené and Inuit waves) is also consistent with the data. Choosing between both “consistent” models (or something in between) clearly requires further investigation. 

Tianyuan and East Asian origins
All the above is very much within expectations, although refreshingly clarifying. But there is something in the formal tests (extended data fig. 5) that is most unexpected (but not discussed in the paper). 
The formal f3 tests of ED-fig.5 a to e fall all within reasonable expectations. Maybe the most notable finding is that, after all, the pre-Inuit people of the Dorset culture (represented by the Saqqaq remains) left some legacy in Greenland, but they also show some extra affinity with several Siberian populations (notably the Naukan, Chukchi, Koryak and Yukaghir, in this order) before to any other Native Americans, including Aleuts). 
But the really striking stuff is in figs. f and g, where it becomes obvious that the Tianyuan remains of Northern China show not a tad of greater affinity to East Asians (nor to Native Americans) than to West Eurasians. Also two East Asian populations (Tujia and Oroqen) are considerably more distant than the bulk of East Asian peoples to Tianyuan but also to Aznick.
Extended Data Figure 5 | Outgroup f3-statistics contrasted for different combinations of populations. (…) f, g, Shared genetic history with Anzick-1 compared to shared genetic history with the 40,000-year-old Tianyuan individual from China.
This is very difficult to explain, more so as Tianyuan’s mtDNA haplogroup B4’5 is part of the East Asian and Native American genetic pool, and the authors make no attempt to do it. 
The previous study by Qiaomei Fu et al. (open access) placed Tianyuan’s autosomal DNA near the very root of Circum-Pacific populations (East Asians, Native Americans and Australasian Aborigines) but after divergence from West Eurasians:
From Qiaomei Fu 2013
They even had doubts about the position of Papuans (the only Australasian representation) in that tree, which they suspected an artifact of some sort.
Since I saw that graph (h/t to an anonymous commenter at Fennoscandian Ancestry) I am squeezing my brain trying to figure out a reasonable explanation, considering that the formal f3 test has almost certainly more weight than the ML tree made with an algorithm. 
My first tentative explanation would be to imagine a shared triple-branch origin for Tianyuan, East Asians and West Eurasians, maybe c. 60 Ka ago (it must have been before the colonization of West Eurasia), to the exclusion of other, maybe isolated, ancient populations, whose admixture with the ancestors of the Tujia, Oroqen and Melanesians (maybe via Austronesians?) causes those striking low affinity values for these.
This would be a similar mechanism to the one explaining lower Tianyuan (and generally all ancient Eurasian) affinity for Palestinians (incl. Negev Bedouins) and also the Makrani, who have some African admixture and (in the Palestinian case) also, most likely, residual inputs from the remains of the first Out-of-Africa episode in Arabia.
However to this day we have no idea of which could be those hypothetical ancient isolated populations of East Asia. In normal comparisons such as ADMIXTURE analysis the Tujia and Oroqen appear totally normal within their geographic context, but this may be an artifact of not doing enough runs to reach higher K values, according to the cross-validation test, much more likely to discern the actual realistic components. 
The matter certainly requires further research, which may well open new avenues for the understanding the genesis of Eurasian populations, particularly those from the East.
 

Mitochondrial lineages from Myanmar

Myanmar, also known as Burma, has been one of those blind spots in the mapping of human genetics. Finally now we get to know something about the peoples of this SE Asian multiethnic state, although there are limitations because the sampling was performed among refugees in Thailand.
Monica Summerer et al., Large-scale mitochondrial DNA analysis in Southeast Asia reveals evolutionary effects of cultural isolation in the multi-ethnic population of Myanmar. BMC Evolutionary Biology 2014. Open accessLINK [doi:10.1186/1471-2148-14-17]

Abstract


Background


Myanmar is the largest country in mainland Southeast Asia with a population of 55 million people subdivided into more than 100 ethnic groups. Ruled by changing kingdoms and dynasties and lying on the trade route between India and China, Myanmar was influenced by numerous cultures. Since its independence from British occupation, tensions between the ruling Bamar and ethnic minorities increased.


Results


Our aim was to search for genetic footprints of Myanmar’s geographic, historic and sociocultural characteristics and to contribute to the picture of human colonization by describing and dating of new mitochondrial DNA (mtDNA) haplogroups. Therefore, we sequenced the mtDNA control region of 327 unrelated donors and the complete mitochondrial genome of 44 selected individuals according to highest quality standards.


Conclusion


Phylogenetic analyses of the entire mtDNA genomes uncovered eight new haplogroups and three unclassified basal M-lineages. The multi-ethnic population and the complex history of Myanmar were reflected in its mtDNA heterogeneity. Population genetic analyses of Burmese control region sequences combined with population data from neighboring countries revealed that the Myanmar haplogroup distribution showed a typical Southeast Asian pattern, but also Northeast Asian and Indian influences. The population structure of the extraordinarily diverse Bamar differed from that of the Karen people who displayed signs of genetic isolation. Migration analyses indicated a considerable genetic exchange with an overall positive migration balance from Myanmar to neighboring countries. Age estimates of the newly described haplogroups point to the existence of evolutionary windows where climatic and cultural changes gave rise to mitochondrial haplogroup diversification in Asia.

The main sampled ethnic group are the Karen, who live at the border with Thailand, but the Bamar or Burmans, the largest ethnic group, were also sampled in big numbers. 
Fig. 2.- Origin of samples and mitochondrial haplogroup distribution of Southeast Asian populations. Although most of the study participants originated from Karen State (red), a broad
sample spectrum from nearly all divisions and states of Myanmar (a) was included in this study. b shows the haplogroup distributions of populations from Myanmar and four other Southeast
Asian regions. In the white insert box the haplogroup heterogeneity of two ethnic
groups of Myanmar is illustrated. The hatched area in the map surrounding the border
between Myanmar and Thailand shows the main population area of the Karen people. The
Bamar represent the largest ethnic group (68%) in Myanmar. The size of the pie diagrams
corresponds to sample size.
The smaller samples are only detailed in the supplementary data for what I have seen, so I will not discuss them right now (maybe in an update?). 
Overall all SE Asians including the Southern Han from Hong-Kong appear similar in broad terms. Excepted Laos, this relative similitude is quite apparent in figure 3:
Fig. 3.- Multi-dimensional scaling plot of pairwise Fst-values and haplogroup distribution
of populations from Myanmar and 12 other Asian regions.
A distinct geographic pattern appeared in the multi-dimensional scaling plot (Stress = 0.086;
R2 = 0.970) of pairwise Fst-values: The Myanmar sample fitted very well within the Southeast
Asian cluster, the Central Asian populations formed a second cluster, the Korean sample
represented East Asia, the Afghanistan population was representative for South Asia
and Russia symbolized Western Eurasia. The main haplogroup distributions are displayed
as pie charts. The size of the pie diagrams corresponds to sample size. The proportion
of N-lineages (without A,B and R9’F) increases from very low percentages in Southeast
and East Asia over 50% in Central Asia to more than 75% in Afghanistan and 100% in
the sample of Russian origin. The proportion of the American founding haplogroups
A,B,C and D displayed an interesting pattern: from inexistent in Russians it increased
to more than 50% in East Asian Korea.
Looking at the particular differences in haplogroup frequencies, I’d say that the Thai are quite unremarkable, while the other populations show some peculiarities:
  • Karen: higher frequencies of R9/F, A, C and G
  • Bamar: much higher M* (and extremely diverse)
  • Laotian: higher frequencies of B and M7
  • Vietnamese: more B and N*
  • South Han (Hong-Kong): more D
It is very notable the high diversity of paragroup M* among the Bamar. The authors notice that not more than three individuals shared each different subhaplogroup, what points to a very high diversity within haplogroup M. I don’t have time right now to ponder the various lineages, some of which are newly described, but I probably will in the future, because, together with the high diversity in NE India, they have the potential of shifting the paradigm of Asian colonization by H. sapiens a bit towards the East.
The various M* and other novel haplogroups described in Myanmar is shown in fig. 4. Haplogroups M90 and M91 are new basal M sublineages, along with three other unnamed private lineages, which also appear as basal. Also M20a, M49a and G2b1a are new sublineages further downstream. Within N/R, another newly described lineage is B6a1.
The Bamar are extremely diverse not just within M*:

… the haplogroup composition of Bamar
was exceptionally diverse with 80 different haplogroups and a maximum of 6 samples
in the same haplogroup (Figure 4).

On the other hand, the Karen show the signs of genetic isolation instead, with large concentrations in the same haplogroups.
Interestingly, the authors think that rather than being a receiver, Myanmar was a major source of population to its neighbors:

Migration analyses of Myanmar and four Southeast Asian regions displayed a vivid exchange
of genetic material between the countries and demonstrated a strong outwards migration
of Myanmar to all analyzed neighboring regions (for details see Additional file 4: Table S4).

This influence is most intense to Laos, Thailand and South China, while things are more balanced regarding Vietnam instead.
 

Homo sapiens was in China before 100,000 years ago!

This finding consolidates the recent dating of African-like industries of India to c. 96,000 years ago, as well as other previous discoveries from mostly China, and, jointly, they totally out-date not just the ridiculous “60 Ka ago” mantra for the migration out-of-Africa (which we know is dated to c. 125,000 years ago in Arabia and Palestine) but also the previous estimates of c. 80,000 years ago for India (Petraglia 2007).
Guanjung Shen et al., Mass spectrometric U-series dating of Huanglong Cave in Hubei Province, central China: Evidence for early presence of modern humans in eastern Asia. Journal of Human Evolution, 2013. Freely accessible at the time of writing thisLINK [doi:10.1016/j.jhevol.2013.05.002]

Abstract


Most researchers believe that anatomically modern humans (AMH) first appeared in Africa 160-190 ka ago, and would not have reached eastern Asia until ∼50 ka ago. However, the credibility of these scenarios might have been compromised by a largely inaccurate and compressed chronological framework previously established for hominin fossils found in China. Recently there has been a growing body of evidence indicating the possible presence of AMH in eastern Asia ca. 100 ka ago or even earlier. Here we report high-precision mass spectrometric U-series dating of intercalated flowstone samples from Huanglong Cave, a recently discovered Late Pleistocene hominin site in northern Hubei Province, central China. Systematic excavations there have led to the in situ discovery of seven hominin teeth and dozens of stone and bone artifacts. The U-series dates on localized thin flowstone formations bracket the hominin specimens between 81 and 101 ka, currently the most narrow time span for all AMH beyond 45 ka in China, if the assignment of the hominin teeth to modern Homo sapiens holds. Alternatively this study provides further evidence for the early presence of an AMH morphology in China, through either independent evolution of local archaic populations or their assimilation with incoming AMH. Along with recent dating results for hominin samples from Homo erectus to AMH, a new extended and continuous timeline for Chinese hominin fossils is taking shape, which warrants a reconstruction of human evolution, especially the origins of modern humans in eastern Asia.

The range of dates for the teeth is ample but the oldest one is of 102.1 ± 0.9 Ka ago. Other dates are very close to this one: 99.5 ± 2.2, 99.3 ± 1.6, 96.8 ± 1.0, etc. (see table 1), so there can be little doubt about their accuracy. 
The Huanglong teeth (various views)
 
Now, how solidly can these teeth be considered to belong to the species Homo sapiens? Very solidly it seems:

The seven hominin teeth from Huanglong Cave have been assigned to AMH
mainly because of their generally more advanced morphology than that of H. erectus and other archaic populations (Liu et al., 2010b),
especially in terms of the crown breath/length index. These teeth also
lack major archaic suprastructural characteristics listed by Bermúdez de Castro (1988)
for eastern Asian mid-Pleistocene hominins, such as “strong tuberculum
linguale (incisors), marked lingual inclination of the buccal face
(incisors and canines), buccal cingulum (canines and molars), wrinkling
(molars), taurodontism (molars), swelling of the buccal faces (molars)”
(Tim Compton, Personal communication). However, in their roots, these
teeth still retain a few archaic features, being more robust and
complicated than those of modern humans (Liu et al., 2010b).

Zhirendong jaw
Let’s not forget that further South in China, in Zhirendong, a “modern” jaw was found and dated to c. 100,000 years ago as well.
As for the so-called “molecular clock”:

The new timeline for human evolution in China is in disagreement with
the molecular clock that posits a late appearance for AMH in eastern
Asia (e.g., Chu et al., 1998).

… too bad for the “clock”, because a clock that doesn’t inform us of time with at least some accuracy is totally useless.
 
 

Homo sapiens from Central China dated to 81-101 Ka BP

I just received notice (h/t David) of this most important finding and dating:
Guanjun Shen et al., Mass spectrometric U-series dating of Huanglong Cave in Hubei Province, central China: Evidence for early presence of modern humans in eastern Asia. Journal of Human Evolution 2013. Pay per viewLINK [doi:10.1016/j.jhevol.2013.05.002]

Abstract


Most researchers believe that anatomically modern humans (AMH) first appeared in Africa 160-190 ka ago, and would not have reached eastern Asia until ∼50 ka ago. However, the credibility of these scenarios might have been compromised by a largely inaccurate and compressed chronological framework previously established for hominin fossils found in China. Recently there has been a growing body of evidence indicating the possible presence of AMH in eastern Asia ca. 100 ka ago or even earlier. Here we report high-precision mass spectrometric U-series dating of intercalated flowstone samples from Huanglong Cave, a recently discovered Late Pleistocene hominin site in northern Hubei Province, central China. Systematic excavations there have led to the in situ discovery of seven hominin teeth and dozens of stone and bone artifacts. The U-series dates on localized thin flowstone formations bracket the hominin specimens between 81 and 101 ka, currently the most narrow time span for all AMH beyond 45 ka in China, if the assignment of the hominin teeth to modern Homo sapiens holds. Alternatively this study provides further evidence for the early presence of an AMH morphology in China, through either independent evolution of local archaic populations or their assimilation with incoming AMH. Along with recent dating results for hominin samples from Homo erectus to AMH, a new extended and continuous timeline for Chinese hominin fossils is taking shape, which warrants a reconstruction of human evolution, especially the origins of modern humans in eastern Asia.

In other words: strong material evidence is quickly piling up in favor of a Homo sapiens “fast” colonization of Southern Asia (and as far NE as Hubei!) around 100 or at least 90 Ka BP. 
See also:
 

Middle Paleolithic industries of African affinity of the Thar Desert go back to c. 96 Ka ago

Again Team Petraglia revealing fascinating evidence on the Middle Paleolithic dispersal of Homo sapiens, and one that fits well the genetic data (speculative “molecular clock” excluded), as well as with the climatic data.
James Blinkhorn et al., Middle Palaeolithic occupation in the Thar Desert during the Upper Pleistocene: the signature of a modern human exit out of Africa? Quaternary Science Reviews, 2013. Pay per viewLINK [doi:10.1016/j.quascirev.2013.06.012]


Abstract

The Thar Desert marks the transition from the Saharo-Arabian deserts to the Oriental biogeographical zone and is therefore an important location in understanding hominin occupation and dispersal during the Upper Pleistocene. Here, we report the discovery of stratified Middle Palaeolithic assemblages at Katoati in the north-eastern Thar Desert, dating to Marine Isotope Stages (MIS) 5 and the MIS 4–3 boundary, during periods of enhanced humidity. Hominins procured cobbles from gravels at the site as evidenced by early stages of stone tool reduction, with a component of more formalised point production. The MIS 5c assemblages at Katoati represent the earliest securely dated Middle Palaeolithic occupation of South Asia. Distinctive artefacts identified in both MIS 5 and MIS 4–3 boundary horizons match technological entities observed in Middle Palaeolithic assemblages in South Asia, Arabia and Middle Stone Age sites in the Sahara. The evidence from Katoati is consistent with arguments for the dispersal of Homo sapiens populations from Africa across southern Asia using Middle Palaeolithic technologies.

Possibly the most strikingly unmistakable evidence for a Homo sapiens affiliation of these findings is the Aterian-like tanged point, which is almost identical to another one found previously in Jwalapuram:

Fig. 4. 1) Tanged point from Jwalapuram 22 (adapted from Haslam et al., 2012); 2 & 3)
Tanged point from Katoati.
Not just Aterian: the, visually less obvious, Nubian technology is also present:

Two Levallois cores from S4 and one from S8 exhibit a mixture of distal divergent and lateral preparation of the flaking surface to produce a distale medial ridge resulting in the removal of prepared points (Fig. 3). These reduction schemes are consistent with descriptions of Nubian Levallois technologies (Rose et al., 2011; Usik et al., 2013).

A single flake from S4 presents a combination of distal divergent and lateral removals on the dorsal surface and a prior removal of a pre-determined pointed flake,indicative of the use of Nubian Levallois strategies (Fig. 3).

Table 2. I added at bottom (red) median OSL ages from table 1.

Zhirendong jaw

In synthesis: groups of unmistakably Homo sapiens with obvious African techno-cultural heritage were already within the modern boundaries of the Indian Federation around 96,000 years ago (CI: 109-83 Ka). This totally debunks Mellars’ and Mishra’s recent claims, the usual “molecular clock” nonsense (that so many people seems willing to believe at face value), and widens significantly the earliest plausible dates for the colonization of Asia (beyond Arabia-Palestine-Persian Gulf) making findings like Zhirendong jaw (the oldest non-Palestinian H. sapiens remains out of Africa, dated to c. 100,000 BP) much more credible.

Until today I was very much in doubt about accepting dates of c. 100,000 years ago for the Asian colonization but since right now I am adopting this model as the most likely one. In other words: it seems clear that the people already settled in Arabia and the Persian Gulf “oasis” did not wait for climatic pressure at the end of the Abbassia Pluvial to send them out in search of new lands: they did it when the pluvial period was still holding the arid gates of Asia open for them.
All the evidence adds up well now. 

_______________________________________

Note: the full paper was available at Academia.edu at the time of writing this:  HERE and HERE.
 

Mellars 2013: second round

As I mentioned before, I have already got copies of the controversial study by Paul Mellars et al., which argues for a very late colonization of Eurasia. It includes some aspects not dealt with in the first round, when I could only access the supplemental material. 
Paul Mellars et al., Genetic and archaeological perspectives on the initial modern human colonization of southern Asia. PNAS 2013. Pay per view (6-month embargo) → LINK [doi:10.1073/pnas.1306043110]
Maybe the most important is the very striking visual comparison between proto-LSA African microlithic industries and post-UP South Asian microlithic ones:

While it is maybe easy to dismiss the patterns drawn on ostrich shells in Africa and South Asia as not really looking the same at all and therefore likely coincidence, the visual comparison of the industries is much harder to reject. It does indeed pose a mysterious apparent link similar to others that are hard to explain like the similitude between Chatelperronian and Gravettian (not so long ago treated together as “Perigordian”) or the hammering insistence by some rather marginal academics on the similitudes between the SW European Solutrean culture and the (much more recent) North American Clovis industry. 
Sure: impressive and intriguing. But when it comes to chronology the Mellars hypothesis seems to fail terribly. While the African microliths are pre-LSA and therefore from before ~49,000 years ago in all cases, the South Asian ones only show up mostly since c. 34-38,000 years ago, more than ten millennia later. Mellars makes this figure 40-35 Ka and then just 40 Ka for the following graph, which in fact misrepresents Petraglia’s model and data in a key issue (see below):

It must be emphasized here that Petraglia’s data and model, at least for what I know it, implies an hiatus between c. 110 Ka and c. 80 Ka BP, hiatus for which there is no archaeological data of any kind in South Asia. Therefore neither side graph should suggest continuity to the past before ~80 Ka, allowing at most for a highly hypothetical dotted line (as in Petraglia 2010):

Also there is nothing in Petraglia’s work that could suggest discontinuity at the Toba ash layer, as suggested by Mellar’s version, rather the opposite: continuity is very apparent in Jwalapuram:

Jwalapuram industries (from Petraglia 2007)

Quite conveniently Mellars ignores Petraglia’s data again, which suggest continuity before and after microlithism in Jurreru Valley and then also finds a transition towards UP (“blade and bladelet”, as well as “backed artifacts”) technologies since c. 34 Ka BP. 
But regardless, I’m pretty sure that Prehistory-savvy readers have already noticed a major issue in all this chronology: we are talking of dates that are almost 20,000 years after the colonization of West Eurasian by H. sapiens with “Aurignacoid” technologies, which are dated to before 55 Ka BP in Palestine (OSL), to c. 49 Ka BP in Central Europe and to c. 47 Ka BP in Altai (C14 calibrated). 
And those who are also familiar with Eurasian population genetics are by now shaking their heads in disbelief and claiming to heaven and hell alike. Because West Eurasians derive, at a late relative date, from Tropical Asians and therefore, if our core ancestors were already separated before 55 Ka BP, there is just no room for the Tropical Asian (and Australasian) expansion that must have preceded the Sapiens colonization of the West Eurasian Neanderlands.
(Those unfamiliar with the basics of Eurasian population genetics, see here).
So there is no way that the Out of Africa migration could be dated to just c. 55 Ka BP, as Mellars does (after grabbing hard the burning nail of conjectural coastal sites now under the sea, which would have to account for some 15-20,000 years of Eurasian prehistory on their own).
In fact it is also impossible from the viewpoint of Australian chronology, which again needs to go after the settlement of Tropical Asia but surely before that of West Eurasia. 
So, regardless of the striking visual comparison between African and Indian industries, which is no doubt the “bunny in the hat” here, the Mellars hypothesis simply doesn’t stand. 
Was there another cultural (surely not demic) flow from Africa to South Asia c. 40-35 Ka BP? Maybe. Or maybe it is just one of the many hard-to-explain coincidences in stone industry design. But whatever it is, it just cannot be the Out-of-Africa migration, unless one is ready to accept that Aurignacian and related European rock art, as well as Australian rock art, for example, are the product of archaic homo species (something that I am sure that Mellars won’t admit to: it just goes against his “modern human behavior” prejudices). And, even then, it just doesn’t add up either.

PS- Petraglia himself finds Mellar’s alternative model untenable. From ABC Science (emphasis mine):

… Professor Michael Petraglia, an archaeologist from the University of Oxford disputes Richards’ and Mellars’ argument. 

Petraglia says there’s not enough evidence to rule out an earlier colonisation before the eruption of Mount Toba. 

“The research reported by Mellars and colleagues is riddled with problems,” he says. 

Petraglia says that the similarity between tools used in Africa
60,000 years ago and those from Asia dating to around 35,000 years ago
is not a consequence of direct migration.


“These toolkits are separated in time by more than 20,000 years and distances exceeding several thousand miles.” 

He questions the evidence supporting a migration along the coast. He
says that surveys of ancient shorelines have not revealed any evidence
for human settlements anywhere along the Indian Ocean shore between
55,000 and 50,000 years ago.

He also says genetic dating should be treated cautiously. 

“Most geneticists will admit that genetic dating of the out-of-Africa
event is tenuous, at best. Published genetic ages for out-of-Africa
range anywhere between 45,000 to 130,000 years ago.

Petraglia
says his team is currently conducting archaeological fieldwork in
Arabia, India and Sri Lanka they expect will show that the story of
human dispersal from Africa is complex.

“What we can agree on is that little research in these key geographic
regions has been conducted and much more evidence needs to be collected
to support or refute the different theories,” says Petraglia.

 

Mellars challenges the ‘early out of Africa’ model

I do not have yet access to this potentially key paper, so first of all I want to make an appeal here to share a copy with me (→ email address). Thanks in advance. Update: got it (thanks to all who shared, you people are just great!) I will review it again as soon as possible.

Update (Jun 18): complementary review of the full paper now available here.

Paul Mellars et al., Genetic and archaeological perspectives on the initial modern human colonization of southern Asia. PNAS 2013. Pay per view (6-month embargo) → LINK [doi:10.1073/pnas.1306043110]

Abstract

It has been argued recently that the initial dispersal of anatomically modern humans from Africa to southern Asia occurred before the volcanic “supereruption” of the Mount Toba volcano (Sumatra) at ∼74,000 y before present (B.P.)—possibly as early as 120,000 y B.P. We show here that this “pre-Toba” dispersal model is in serious conflict with both the most recent genetic evidence from both Africa and Asia and the archaeological evidence from South Asian sites. We present an alternative model based on a combination of genetic analyses and recent archaeological evidence from South Asia and Africa. These data support a coastally oriented dispersal of modern humans from eastern Africa to southern Asia ∼60–50 thousand years ago (ka). This was associated with distinctively African microlithic and “backed-segment” technologies analogous to the African “Howiesons Poort” and related technologies, together with a range of distinctively “modern” cultural and symbolic features (highly shaped bone tools, personal ornaments, abstract artistic motifs, microblade technology, etc.), similar to those that accompanied the replacement of “archaic” Neanderthal by anatomically modern human populations in other regions of western Eurasia at a broadly similar date.

A review has been published at Live Science.

South Asian artifacts from ~30-50 Ka BP.

By “genetic evidence” they obviously mean “molecular clock” nonsense, so it is not evidence at all but mere speculation. However I am indeed very interested in knowing in detail what they mean by “archaeological evidence”, because they seem to get into direct confrontation with much accumulated evidence, first and foremost all of Petraglia’s research in both India and Arabia but also with the quite strong evidence for pre-60 Ka human presence in Australia and growing evidence for pre-60 Ka modern humans in SE Asia (in some cases even as old as 100 Ka). 
It must be said that Paul Mellars has been criticized before a lot for several reasons but very especially for his adherence to the quite speculative “modern human behavior” conjecture and, relatedly, bigotric attitudes against Neanderthal intellectual capabilities, based on nothing too solid. Therefore I’m generally skeptic about what Mellars has to say on this matter because this kind of conclusion is what one would expect from him. 
However Mellars is certainly a distinguished academic and, even if prejudiced and stuck to his own old-school and somewhat Eurocentric interpretations, he knows his trade as archaeologist and prehistorian. So he may be onto something, even if it is not exactly what he wants us to believe. 
For example, it is not impossible that this research may have, unbeknown to the authors, found evidence of a secondary OoA wave (maybe related to the spread of Y-DNA D and mtDNA N?) or even a distinctive evolution in Southern Asian technology prior to the expansion of Western Eurasia. 
It is interesting that they suggest that the 80-60/50 Ka toolkits of India would have been made by Neanderthals, when they are not describing them at all as Mousterian, the almost exclusively Neanderthal techno-culture, or Mousterian-related.
I have some difficulties judging before reading the whole study. However the supplemental material (quite extensive) is freely accessible and for what I can see there:
  1. They dedicate much text to attempt to justify a particular version of mainstream “molecular clock” hypothesis, which are clearly broke in my understanding. The kind of arguments “rebated” are more or less what I have been putting forward since many years ago. Ironically their “molecular clock” estimates make N and R much older than M, what I absolutely oppose (just count mutations downstream of the L3 node).
  2. No real attention is given instead to the geographical structure/distribution of major mtDNA haplogroups, only mentioned in relation to “molecular clock” speculations.
  3. The criticism of the African affinity of the Jwalapuram (Jurreru Valley) cores (Petraglia 2007) focuses on dismissal of any possibility of comparison, rather than on alternative comparisons. 
  4. Another “criticism” is that there is no apparent connection between Jwalapuram and the Nubian Complex (why there should be any?, it is not the only East African techno-culture, nor the only group that shows indications of traveling to Arabia in the Abbassia Pluvial).
  5. Also it is “criticized” that the most comparable African culture, Howiesons Poort) is not recorded before c. 71 Ka BP (what IMO may indicate late cultural dispersals to Southern Africa from East Africa, for example, but, hey!, Mellars is fencing off balls like crazy at his conservative goal). 
  6. They find clear similitudes between Indian and African microlithic industries (apparently related to the development of “mode 4” in both areas, as well as in West Eurasia). Indian industries are dated to c. 38-40 Ka BP, while African ones are dated to c. 49 Ka BP (Kenya) or later. However West Eurasian ones have dates as old as 55 Ka BP (not for Mellars, who remains stuck in older date references which he describes as ∼40–45 ka [calibrated (cal.) before present (B.P.)]), what really suggest that we are talking here not of the “out of Africa” but of the West Eurasian colonization process (necessarily from further into Asia, genetic phylo-geographic structure demands) with offshoots to the nearby regions. 
  7. Another element of late Africa-India “similitude” they find is “the remarkable, double bounded criss-cross design incised on ostrich eggshell”, dated in India (Patne) to at least ∼30 ka (cal. B.P.), much earlier in South Africa. For Mellars this is beyond the range of either pure coincidence or entirely independent and remarkably convergent cultural evolutionary processes. Hmmm, really? Or are we before a clear case of wishful thinking as happens with the Solutrean-Clovis relationship hypothesis? Isn’t it 30 Ka BP anyhow well beyond any reasonable expectations for the OoA time frame, including Mellar’s own conjectures?
  8. Mellars accepts the paradox that the geographical limits of these highly distinctive microblade and geometric microlithic technologies are confined to the Indian subcontinent, with no currently documented traces of these technologies in regions farther to the east. And then makes up excuses for it, such as biological and cultural bottlenecks caused by “founder effects”, mysteriously leading to a loss or simplification of cultural and technological know-how, as well as fininding new and contrasting environments (in the same latitudes?!)
  9. Even in the case of Arabian colonization, Mellars shows to be in a very defensive attitude, admitting only to the reality of the Palestinian sites with clearly modern skulls, as well as to the area of Nubian Complex colonization (on whose peculiarities he insists a lot, as if it would be the only expression of the wider MSA techno-complex), disdaining all the other MSA colonization areas and, often ill-defined, variants.
In brief, for what I could see in the supplemental material, along with some potentially interesting references to the relative cultural community spanning from East Africa to South Asia at the time of emergence of “mode 4” industries, it seems that Mellars and allies are essentially putting the cart (their models) before the horses (the facts), what is bad science. 
In 2008, Zilhao and d’Errico angrily accused Mellars of being an obsolete armchair prehistorian (different words maybe, same idea). Back in the day I was tempted to support Mellars but nowadays I must agree that he is clearly stuck in a one-sided interpretation of prehistory whose time is long gone. Whatever the case I welcome the debate and can only hope that will help to produce even more evidence to further clarify the actual facts of the Prehistory of Humankind.